Generally, an engine of a vehicle combusts fuel mixed with air at an appropriate ratio to generate thermal energy and converts the thermal energy to mechanical energy.
Exhaust gas of high temperature and pressure is produced during the process of the combustion of an engine, and the exhaust gas is collected by an exhaust manifold and is then guided to an exhaust pipe, and harmful components of the exhaust gas may be removed while passing through a catalytic converter and noises are reduced while passing through a muffler.
The exhaust manifold includes an inlet which is formed at an upstream thereof to be connected to a combustion chamber and an outlet which is formed at a downstream thereof.
A conventional exhaust manifold is configured to have a plurality of inlets which are divided respectively for combustion chambers of an engine so as to prevent the deterioration of output performance due to the interference between gases exhausted from the combustion chambers after the combustion. Accordingly, gases exhausted from the respective combustion chamber of an engine flow respectively into a plurality of inlets and move in the respective tubes. Such tubes are unified before being exhausted, so the outlet is formed as one.
However, since the inlet is provided as the plurality, the interference between gases exhausted from different combustion chambers can be prevented, but since the inlet and the tube should be provided with the same number as the combustion chambers, there are problems in that the productability and the economic feasibility are deteriorated, and the possibility of fault may be increased due to the assembly of many parts, and the workability may be decreased due to the greater spatial occupation, and the exterior appearance may be poor.